On August 24th at 12:17 UT, NASA’s Solar Dynamics Observatory recorded this M5.6-category explosion near the eastern limb of the sun.
The source of the blast was sunspot AR2151. As the movie shows, an instability in the suspot’s magnetic canopy hurled a dense plume of plasma into space. If that plasma cloud were to hit Earth, the likely result would be strong geomagnetic storms. However, because of the sunspot’s location near the edge of the solar disk, Earth was not in the line of fire.
Even so, the flare did produce some Earth effects. A pulse of extreme UV radiation from the explosion partially ionized our planet’s upper atmosphere, resulting in a Sudden Ionospheric Disturbance (SID). Waves of ionization altered the normal propagation of VLF (very low frequency) radio transmissions over the the dayside of Earth, an effect recorded at the Polarlightcenter in Lofoten, Norway: data.